What does the Vaillant F.28 fault code mean?

Your boiler is trying to start up, but it is failing to ignite the gas safely.

How much does it cost to fix Vaillant error code F.28?

Typical repair cost for the Vaillant F.28 fault is £150-350 including labour.

Vaillant F.28 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

Appliance does not start: Attempts to ignite during start failed | Faults in the gas supply such as: - Gas meter or gas pressure detector defective - Air in gas - Gas flow pressure too low - Fire protection tap has disengaged Faults in the gas fitting (main gas magnet or operator defective), wrong gas setting, igniter (ignition transformer, ignition cable, ignition plug) defective, ionisation current stopped (cable, electrode), faulty earthing in appliance, electronics defective

From this model's manual

Verified against the Vaillant/Vaillant Ecotec Plus Pro 839592 00 2004 installation & service manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Boiler cover options

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Related fault codes

F.29View →F.75View →

All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

Seeing a different code? Every code this model can display, in one place.

d.00 d.01 d.02 d.03 d.05 d.06 d.07 d.08 d.09 d.10 d.11 d.17 d.18 d.19 d.22 d.23 d.25 d.26 d.30 d.33 d.34 d.35 d.36 d.40 d.41 d.44 d.47 d.50 d.51 d.60 d.61 d.64 d.65 d.67 d.68 d.69 d.70 d.71 d.72 d.73 d.75 d.76 d.77 d.78 d.80 d.81 d.82 d.83 d.84 d.90 d.91 d.93 d.97 F.00 F.01 F.02 F.10 F.11 F.13 F.20 F.22 F.23 F.24 F.27 F.29 F.32 F.60 F.61 F.62 F.63 F.64 F.65 F.70 F.71 F.72 F.73 F.74 F.75 F.76 P.1 P.2 P.3 P.4 P.5 P.6 S.00 S.01 S.02 S.03 S.04 S.05 S.06 S.07 S.08 S.10 S.11 S.13 S.14 S.15 S.16 S.17 S.20 S.21 S.22 S.23 S.24 S.25 S.26 S.27 S.28 S.30 S.31 S.32 S.34 S.36 S.53 S.54 S.76

Your boiler is trying to start up, but it is failing to ignite the gas safely.

What the manual says

Engineer required

Avoid the next call-out bill

Related fault codes

All 119 fault codes on the ecoTEC plus 612 VU GB 126/3-5

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